Sewing machine



Aug; s, 1939 C. W. MUELLER SEWING MACHINE Filed Jan. 29, 1937 '4 Sheets-Sheet 1 Sum/M41 C. W. MUELLER SEWING MACHINE Aug. s, 1939 Filed Jan. 29, 1937 4 Sheets-Sheet 2 Aug. 8, 1939 c. w. MUELLER SEWING MACHINE Filed Jan. 29, 1937 4 SheetS-She-ejlI -ivrwffwl www WN. l Kv/r//r/r//f//r/r mn l# Char/es W Mue//er' Tiff Aug- 8, 1939 C. w. MUELLER 2,168,740

SEWING MACHINE Filed Jan. 29, 1937 4 sheets-sheet 4 mi in @BMJ Patented ug. 8, 1939 UNITED ATENT OFFI SEWING MACHINE Application January 29, 1937, Serial No. 123,059

5 Claims.

This invention relates to new and useful improvements in sewing machines generally, although more particularly to a blind stitch sewing machine of the post type such as is shown in my prior Patents 2,038,848 and 2,038,849 issued Apr. 28, 1936, and in my co-pending application Serial No. 127,983, led Feb. 26, 1937, for improvements in Sewing machines.

In said patents and application, the base arm extends laterally from the standard and thence forwardly to the post, and consequently when the machine is set on a bench the laterally extending portion of the base arm precludes the sewing of small articles, such as infants dresses, etc.

The principal object of the present invention is to provide a main frame wherein the base arm extends forwardly and thence laterally to the post thereby permitting the bench to be cut away in rear of the post to provide the necessary clearline 3 3 of Figure 2,

Figure` 4 is a vertical section taken through the standard and forwardly extending base arm, and

Figure 5 is a Vertical section taken through the post.

Like reference numerals designate corresponding parts throughout the several figures of the drawings.

By reference to the accompanying drawings, it will be seen that my invention includes a main frame A which comprises a standard 5 having an upper horizontal arm 6 extending laterally from the upper end thereof and terminating in a forwardly extending upper arm 1, and a base arm 8 i which extends forwardly from the lower end of the standard and terminates in a laterally extending arm 9 disposed in front of and in parallel relation to the upper arm 6, the free end of the base arm 9 being disposed below the free end of the upper arm l. v

Rigidly fixed to the free end of the upper arm is a horizontal presser foot B having a centrally located opening.

Journaled in the upper end of the standard 5 and in the upper arm 6 is a main shaft I I. Journaled in the upper arm I and extending longitudinally thereof is an oscillatory needle shaft I2 having a needle arm I3 fixed to its front end. Attached to the needle arm I3 is a curved needle I4 which reciprocates across said opening of the 10 foot. The needle shaft I2 is oscillated from the main shaft II by the usual connections. A looper or spreader I5 cooperates with the needle I4 in the usual manner to form single thread chain stitches, although any other type of complemental stitch forming mechanism may be employed if desired. f

Located directly under the pressor foot B and movable upwardly towards the foot and downwardly therefrom, is a work supporting post C. 20 The post C is rectangular in horizontal cross section and is mounted in a 2-part well or housing D, the right hand part or wall I6 being rigid with and projecting upwardly from the forward end of the base arm 9, and the left hand part or wall II constituting ya removable cover for the post and certain movable parts which are located therein. The upper edge of the housing D is located below and in spaced relation to the presser foot B, and the upper portion of the post C projects upwardly above said upper edge. 'Ihe walls I6, I'I of the housing are Conjointly formed with an opening to freely receive the post C. The post C is guided in its vertical movements by front and rear vertical guide bars I8, I9. .m

Carried by the post C and bodily movable up 'L and down therewith are a work clamp E and a ridge-forming element F.

The ridge forming element F which projects nodes of material upwardly through the slot of ,m the presser foot into needle penetrating position, comprises a stepped disc which is fixed to a transverse rock shaft 20 journaled in the post C whereby the disc may be oscillated forwardly and rearwardly. 'I'he axis of the disci. e., the shaft 20, is 45 located below and in parallelism with the path of movement of the needle I4, or in other words, at right angles to the line of feed. It will be also observed that the disc is located directly below the needle shaft I2, and in register with the open- 50 ing of the presser foot B, and is adapted to project intermittently nodes of material upwardly through said opening into needle penetrating position.

'I'he disc is reciprocated from the main shaft I I by a train of mechanism which includes a reduction gear coupling X which is mounted in the standard 5 and is fully disclosed in my prior Patent 2,038,849 and in my co-pending application referred to above. A rock shaft 2| is journaled in the rear end of the base arm 8 directly below the standard 5,and a bell crank lever having a horizontal arm 22 and a vertical arm 23 is xed to said shaft. A pitman 24 has its upper end operatively connected to the reduction gear coupling X and its lower end pivotally connected to the horizontal arm 22. A rock shaft 25 extends longitudinally within the base arm 9 and is provided at its right hand end with an upstanding rock arm 26 which is connected by a link 21 to the vertical arm 23. The left hand end of the rock shaft 25 is located in rear of the post C and is provided with a rock arm 28. A vertically disposed lever 28 is fulcrumed intermediate its ends on the post C and a link 3B connects the rock arm 28 with the lower end of said lever. 'Ihe upper end of said lever is connected by a link 3| to the disc F. Thus it will be seen that the disc is reciprocated from the main shaft il by a train of mechanism which includes the rock shaft 25 which extends longitudinally within the base arm 9 and a driving link 2 therefor which extends along and within the base arm 8.

It is desirable to provide means for depressing the post C for the purpose of inserting work under the foot or withdrawing work therefrom. The post is provided with a depending lug 32 and a toggle is interposed between and connected to the lug and to the base arm 9. 'Ifnis toggle includes a bell crank lever 33 which includes a substantially vertical arm 34 and a forwardly extending and substantially horizontal arm 35. The lower end of the arm 34 is fulcrumed on an eccentric 36 which is xed to a horizontal shaft 3l which extends across the well D and below the post C. The shaft 37 extends longitudinally of the base arm 9 and its right hand end projects into the base arm 8. A normally vertically disposed link 38 is pivotally connected at its upper end by a pin 39 to the lug 32 and at its lower end by a pin 40 to the upper end of the toggle lever arm 34, the pin 4|) being rigidly secured to the link 38 by a set screw 4|. A coil spring 42 is disposed around the projecting end of the pin 48, one end of the spring being anchored in a transverse slot 43 formed in the end of the pin and the other end of the spring engaging under a stop pin 44 xed to the bell crank lever 33. The spring 42 functions to yieldably retain the toggle elements 34, 38 in their vertical or locked positions. A chain 45 adapted to be connected to a treadle or knee-press, has its upper end connected to the outer end of the horizontal arm 35 of said bell crank lever. Thus, upon operation of the kneepress or treadle the toggle will be broken and the post C together with the parts mounted thereon, will be depressed to permit the ready insertion or withdrawal of the material, and upon release of said knee-press or treadle the parts will be returned to their normal position by the spring 42.

In order to positively adjust the normal vertical position of the post C and thereby set the machine for materials of different thicknesses, I have provided a hand adjusting shaft 46 which is journaled in a bushing 4l mounted in a tubular bearing bracket 48 secured in an opening 49 formed in the front wall 5|) of the standard 5. A nger knob 5| is rigidly attached to the front end of the shaft 46 and is provided with a series of rearwardly projecting teeth 52 arranged concentrically thereon for engagement with a spring pin 53 mounted in the bearing bracket 48. A pointer 54 is fixed to the bracket 48 and overhangs the knob 5| for cooperation with a series of numerals 55 arranged sequentially on the front face of the knob. The inner end of the bracket 48 is provided with a pair of arms 56, 56 in which is xed a horizontal bearing pin 5l on which is journaled a worm wheel 58 which is in constant mesh with a worm formed on the inner end of the shaft 46 as shown in Figure 4.

A bell crank lever having a horizontal arm 59 and a vertical arm 6|] is fulcrumed on a stub shaft 6| mounted in the rear end of the base arm 8 below the standard 5, the arm 59 being connected by a link 62 with the worm wheel 58. A pinion 63 is fixed to the right hand end of the shaft 3l and a rack bar 64 extends longitudinally with the base arm 8 and has its iear end pivotally connected to said vertical arm 68. The front end of therack bar is disposed below the pinion and is provided with rack teeth 65 which engage the teeth of said pinion. A disc 66 is journaled on the shaft 3'! and carries a pin 6l which forms a support for the front end of the rack bar, A coil spring 68 has one end connected to a pin 69 mounted on the disc and its other end to a pin 'lil mounted on the base arm 8. The disc 86 is in the nature of a lever and the spring 68 exerts a pull on the lever to maintain the rack bar in yieldable engagement with the pinion. Thus when the knob 5I is rotated, the rack bar 64 will be moved endwise, the shaft 3l together with the eccentric 36 will be rotated. and the post C will be raised or lowered, depending on the direction of rotation of the knob. It will therefore be seen that the post adjusting means includes a hand control element mounted on the standard 5, a horizontal shaft 31 which extends longitudinally within the base arms 8 and 9, and a rack bar 64 which extends longitudinally within the base arm 8.

It is of course to be understood that the details of structure and arrangement of parts may be variously changed and modified without departing from the spirit and scope of my invention.

I claim:

1. In a blind stitch sewing machine, a main frame comprising a standard having an upper arm extending laterally therefrom and terminating in a forwardly extending arm, and a base arm extending forwardly from the standard and cooperating with the latter to support the frame and terminating in a laterally extending arm arranged in front of and in parallelism with the laterally extending upper arm, blind stitch forming means including a horizontally reciprocable needle supported on the forwardly extended arm and a movable ridge forming element mounted on the base arm, the free end of the base arm being disposed substantially under the free end of the upper arm.

2. In a blind stitch sewing machine, the combination with a main frame comprising a standard having an. upper arm extending laterally therefrom and terminating in a forwardly extending arm, and a base arm extending forwardly from the standard and cooperating with the latter to support the frame and terminating in a laterally extending arm arranged in front of and in parallelism with the laterally extending upper arm, the free end of the base arm being disposed substantially under the free end of the upper arm, of a horizontal presser foot fixed to the free end of the upper arm, a main shaft journaled in the standard, a stitch forming mechanism including a horizontally reciprocatory needle mounted -on the free end of the upper arm above the foot and having driving connections with the main shaft, a post mounted on the free end of the base arm directly below the foot, a movable ridge forming element mounted on the post for projecting `a ridge of material upwardly through the foot into needle penetrating position, and driving connections between the ridge forming element and the main shaft and extendin-g along the base arm and into the standard.

3. In a blind stitch sewing machine, the combination with a main frame comprising a standard having an upper arm extending laterally therefrom and terminating in a forwardly extending arm, and a base arm extending forwardly from the standard and cooperating with the latter to support the frame and terminating in a laterally extending arm arranged in front of and in parallelism with the laterally extending upper arm, the free end of the base arm being disposed substantially under the free end of the upper arm, of a horizontal presser foot fixed to the free end of the upper arm, a main shaft journaled in the standard, a stitch forming mechanism including a horizontally reciprocatory needle mounted on the free end of the upper arm above the 'foot and having driving connections with the main shaft, a post mounted on the free end of the base arm directly below the foot, a movable ridge forming element mounted on the post for projecting a ridge of material upwardly through the foot'into needle penetrating position, and driving connections between the ridge forming element and the main shaft comprising a rock shaft extending longitudinally within the laterally extending base arm and operatively connected with said ridge formingl element, and operating connections between said rock arm and the main shaft including a link extending longitudinally within the forwardly extending base arm.

4. In a blind stitch sewing machine, the combination with a main frame consisting a standard having an upper arm extending laterally therefrom and terminating in a forwardly extending arm, and a base arm extending forwardly from the standard and terminating in a laterally extending arm arranged in front of and in parallelism with the laterally extending upper arm, the free end of the base arm being disposed substantially under the free end of the upper arm, of a horizontal presser foot fixed to the free end of the upper arm, a post mounted for vertical movements on the free end of the base arm directly below the foot, and means for raising and lowering the post including a rotatable shaft extending longitudinally within the laterally extending base arm, a manually operable means mounted on the standard, and operating connections between the shaft and the manually operable means including a pinion fixed to the shaft and a rack bar engageable with the pinion and extending longitudinally within the forwardly extending base arm.

5. In a blind stitch sewing machine, the combination with a main frame comprising a standard Vhaving an upper arm extending laterally therefrom and terminating in a forwardly extending arm, and a base arm extending forwardly from the standard and terminating in a laterally extending arm arranged in front of and in parallelism with the laterally extending upper arm, the free end of the base arm being disposed substantially under the free end of the upper arm, of a horizontal presser foot fixed to the free end of the upper arm, a post mounted for vertical movements on the free end of the base arm directly below the foot, and means for raising and lowering the post including a rotatable shaft extending longitudinally within the laterally extending base arm, one end of the shaft being disposed directly under the post, an eccentric fixed t0 said end of the shaft and having operative connections with the post, a manually operable means mounted on the standard, and operating connections between the shaft and the manually operable means including a pinion fixed to the shaft and a rack bar engageable with the pinion and extending longitudinally within the forwardly extending base arm.

CHARLES W. MUELLE'R. 

